Is JDK installation required for developing and running Java applications?

To develop Java applications, installing the JDK (Java Development Kit) is essential, as it contains the javac compiler and other tools for writing and compiling code.

To run Java applications, it is sufficient to have the JRE (Java Runtime Environment) installed, which includes the JVM virtual machine and libraries for executing programs.

However, modern JDKs usually include the JRE as well, so often installing the JDK is enough for both development and execution.

Example: if you want to write and compile a program, you need the JDK. If you are simply running an already compiled application, the JRE is sufficient.